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POAVPlayer audio volume over Airplay?
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copied!<p>Does anyone know of a way to adjust an AVPlayer track's volume when it is playing over Airplay? I have tried AVAudioMix and MPVolumeView but neither of them work. I have tried on iOS 5 and iOS 6 and am using the latest xcode 4.5.1. A simple example of this not working is Apple's AVPlayerTestApp which does a simple fade out using setVolumeRampFromStartVolume. This works fine on the device but doesn't if connected through Airplay.</p> <p>In ViewDidLoad I load a track and start it playing (this is all taken from AVPlayerTestApp)</p> <pre><code>AVAudioSession *session = [AVAudioSession sharedInstance]; [session setActive:TRUE error:nil]; [session setCategory:AVAudioSessionCategoryPlayback error:nil]; self.mediaItems = [[[MPMediaQuery songsQuery] items] mutableCopy]; NSURL *anUrl = [[mediaItems objectAtIndex: 0] valueForProperty:MPMediaItemPropertyAssetURL]; AVAsset *asset = [AVURLAsset URLAssetWithURL:anUrl options:nil]; AVPlayerItem *myPlayerItem = [AVPlayerItem playerItemWithAsset:asset]; self.myPlayer1 = [[[AVPlayer alloc] initWithPlayerItem:myPlayerItem] retain]; [myPlayer1 play]; </code></pre> <p>then I have a button which opens an alertview allowing user to set volume and switch on airplay</p> <pre><code>MPVolumeView *volumeView = [[[MPVolumeView alloc] initWithFrame: CGRectMake(10, 37, 260, 20)] autorelease]; UIAlertView *volumeAlert = [[UIAlertView alloc] initWithTitle:@"Volume" message:@"" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil]; [volumeView sizeToFit]; [volumeAlert addSubview:volumeView]; [volumeAlert show]; [volumeAlert release]; </code></pre> <p>then another button which fades out the currently playing track</p> <pre><code>AVAsset *asset = [myPlayer1.currentItem asset]; NSArray *keys = [NSArray arrayWithObject:@"tracks"]; [asset loadValuesAsynchronouslyForKeys:keys completionHandler:^(void) { NSError *error = nil; AVKeyValueStatus trackStatus = [asset statusOfValueForKey:@"tracks" error:&error]; CMTime currentTime; switch (trackStatus) { case AVKeyValueStatusLoaded: if(myPlayer1) { NSArray *tracks = [asset tracksWithMediaType:AVMediaTypeAudio]; NSMutableArray * allAudioParams = [NSMutableArray array]; for (AVAssetTrack *t in tracks) { AVMutableAudioMixInputParameters *params =[AVMutableAudioMixInputParameters audioMixInputParameters]; float fadeOutSeconds = 5; currentTime = [myPlayer1 currentTime]; [params setVolumeRampFromStartVolume: 1.0 toEndVolume: 0.0 timeRange: CMTimeRangeMake(currentTime, CMTimeMakeWithSeconds(fadeOutSeconds, 1))]; [params setTrackID:[t trackID]]; [allAudioParams addObject:params]; } AVMutableAudioMix * zeromix = [AVMutableAudioMix audioMix]; [zeromix setInputParameters:allAudioParams]; [myPlayer1.currentItem setAudioMix:zeromix]; } break; case AVKeyValueStatusFailed: // error occured loading AVAsset NSLog(@"error occured loading AVAsset"); break; case AVKeyValueStatusCancelled: // loading of the AVAsset was cancelled NSLog(@"loading of the AVAsset was cancelled"); break; default: break; } }]; </code></pre> <p>This works as expected on the device and fades the volume when the button is tapped. However, if Airplay is turned on the volume change doesn't get through. Using MPMoviePlayController I can do fades myself which work over Airplay but AVPlayer has less latency over Airplay so I would rather use that.</p> <p>Any help much appreciated.</p>

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